Continuous magnesium hydride production system and production method

Abstract

The invention relates to the field of magnesium hydride production, in particular to a continuous magnesium hydride production system and method. Through optimized process design, a tubular main reaction kettle controls constant temperature and pressure, a double-helix mechanism is arranged in the tubular main reaction kettle to stir and push powder to move directionally, hydrogen and magnesium powder mixed with a catalyst are injected from a top decompression chamber at the inlet end of the reaction kettle, and synthesized magnesium hydride powder is discharged from an outlet at the tail end of the reaction kettle and is output. According to the system for continuously producing magnesium hydride, solid magnesium hydride can be continuously and stably synthesized, the hydrogen content of magnesium hydride can reach 7.6 wt.% at most, compared with a magnesium vapor-hydrogen reaction, the magnesium hydride production method provided by the invention is lower in reaction temperature and controllable in pressure, the conversion efficiency can reach 99.5% at most, and the production cost is low. And industrial large-scale synthesis of magnesium hydride is realized.

Description

Technical Field

[0001] This invention relates to the field of magnesium hydride production, and more particularly to a continuous magnesium hydride production system and method. Background Technology

[0002] Hydrogen energy is considered a mainstream clean energy option for the future. After more than 40 years of industrial development, a complete industrial chain has been established, encompassing hydrogen production, transportation, and utilization. Although hydrogen energy has not yet been fully commercialized and industrialized, its high energy density and clean characteristics have been thoroughly verified. In the early stages, hydrogen transportation relied primarily on high-pressure hydrogen systems, but these systems still suffer from high costs and safety risks, meaning that demonstration hydrogen-powered buses still require government subsidies to maintain their trial operation. This situation has raised concerns about the commercialization of hydrogen energy.

[0003] In innovative research on hydrogen energy technology pathways, scientists have discovered that among all existing forms of hydrogen, including gaseous, liquid, cryogenic liquid hydrogen, methanol, liquid ammonia, organic solvent hydrogen storage, and solid hydrogen storage solutions, magnesium alloy hydrogen storage systems stand out. This system not only produces zero carbon emissions but also boasts the highest hydrogen carrying capacity, reaching 75 kg / m³. 3 It exceeds the 70 kg / m³ of cryogenic liquid hydrogen. 3 (Not taking into account the weight of the cryogenic container), it far exceeds the theoretical value of 25-40 kg / m³ for the highest pressure of high-pressure gaseous hydrogen (100 MPa). 3 (i.e., 5.7% wt, taking into account the weight of the high-pressure gas cylinder). Therefore, magnesium-based solid hydrogen energy has become a recognized new generation of hydrogen energy and has entered the early stage of industrialization, with commercial trials of magnesium-based solid hydrogen already underway.

[0004] However, some problems remain in the industrialization process of preparing magnesium hydride (MgH2) by hydrogenation of magnesium (magnesium alloys), such as high cost, low production efficiency, and quality fluctuations. These problems hinder its rapid industrialization. Nevertheless, with continuous technological advancements and gradual cost reductions, the future of hydrogen energy remains promising, and it is expected to achieve large-scale commercial application in the near future.

[0005] On July 18, 2025, using "magnesium hydride and preparation and spiral and hydrogen and production" as the abstract keywords and allowing synonym expansion, a search was conducted in the China Patent Publication Database. CN119971905A discloses a large-scale magnesium hydride production device and process, relating to the field of magnesium hydride preparation technology, including a magnesium powder buffer tank, a high-temperature and high-pressure hydrogenation reactor, a magnesium hydride buffer tank, and a finished product tank; a feed pipe is provided between the magnesium powder buffer tank and the high-temperature and high-pressure hydrogenation reactor, and the feed pipe is equipped with a first valve; the high-temperature and high-pressure hydrogenation reactor... A double-helix stirring shaft is installed inside the high-temperature and high-pressure hydrogenation reactor, and a second valve is installed on the discharge pipe. A spiral drill bit is installed at the bottom of the double-helix stirring shaft, extending into the discharge pipe and approaching the second valve. The high-temperature and high-pressure hydrogenation reactor is equipped with a high-pressure hydrogen inlet, and several temperature sensors are installed on the inner wall of the reactor. Technical effect: When the first and second valves are closed, high-pressure hydrogen gas is introduced, and magnesium hydride is synthesized during the reverse stirring of magnesium powder by the double-helix stirring shaft; when the second valve is opened, the double-helix stirring shaft rotates forward and drives the magnesium hydride powder to fall from the discharge pipe into the magnesium hydride buffer tank.

[0006] On July 18, 2025, an abstract search was conducted on CNKI (China National Knowledge Infrastructure) for the topic "magnesium hydride and preparation and spiral and hydrogen production", but no relevant literature was found.

[0007] On July 18, 2025, a search was conducted on the website of the United States Patent and Trademark Office for the term "magnesium hydride with preparation with helical with hydrogen gas with production", but no relevant literature was found; the search URL is https: / / ppubs.uspto.gov / pubwebapp / .

[0008] On July 18, 2025, a search was conducted on WIPO's website https: / / patentscope2.wipo.int / for the title "magnesium hydride and preparation and helical and hydrogen gas and production", but no relevant literature was found.

[0009] On July 18, 2025, a search was conducted on the website of the Japan Patent Office (https: / / www.j-platpat.inpit.go.jp / ) for the search term "magnesium hydride and preparation and helical and hydrogen gas and production", but no relevant literature was found.

[0010] It is completely different from the concept of this patent.

[0011] The drawbacks of these technologies are that they cannot preheat hydrogen, cannot be protected by inert gases, and cannot utilize the large amount of heat released from the chemical reaction during the synthesis of magnesium hydride from hydrogen and magnesium to generate electricity. Summary of the Invention

[0012] Purpose of the invention: To provide a more effective continuous magnesium hydride production system and method, the specific purpose of which is described in the detailed implementation section for several substantial technical effects.

[0013] To achieve the above objectives, the present invention adopts the following technical solution:

[0014] A continuous magnesium hydride production system, characterized in that,

[0015] The system includes a tubular main reactor system, which includes a reactor body 16. The reactor body has a multi-layer nested structure, and from the outside to the inside, the multi-layer nested structure consists of an outer shell 22, a water cooling jacket 23, an intermediate wall 24, a hydrogen preheating jacket 25, a thermoelectric power generation system 26, a reactor resistance preheater 27, and an inner wall 28. In the hydrogen cooling jacket and water cooling jacket of the multi-layer nested structure, there are multiple support plates 30 that are welded or glued to the shell plates they contact, so as to support each reactor shell layer to maintain its cylindrical shape and fixed cavity size during operation.

[0016] The inner wall 28 of the reactor is connected to the feeding pressure reduction chamber 15 of the magnesium powder feeding system and is connected to the feeding funnel 13 through the feeding mixing and preheating chamber. The space inside the inner wall 28 of the reactor is connected to the discharge pressure reduction chamber 3 of the magnesium hydride discharge system and is connected to the collection chamber 5 through the discharge cooling box.

[0017] The water cooling jacket 23 connects the cooling water inlet pipe-valve-pressure gauge system 2 and the cooling water outlet pipe 8; the water cooling system is a sandwich-type inner cavity composed of the intermediate wall of the reactor and the outer shell 22 of the reactor, as well as water pumps, valves and pipes, used to provide strong cooling for the intermediate wall; the water cooling system can also maintain the stability of the system during long-term operation and prevent the system from overheating;

[0018] The hydrogen preheating jacket 25 is connected to the hydrogen injection system 12, and the hydrogen preheating jacket 25 is connected to the inner cavity of the inner wall 28 of the reactor at the head of the reactor.

[0019] A vent valve 19 is also arranged on the reactor body 16. The vent valve includes a vent pipe for gas pressure reduction, and a valve system is arranged on the vent pipe.

[0020] A double helix stirring system 1 is arranged in the internal cavity of the inner wall 28 of the reactor. The double helix stirring system 1 is driven by the main motor power source 11 of the double helix system through the main shaft-sealing system 10.

[0021] A further technical solution of the present invention is that a thermoelectric power generation system 26 and a reactor resistance preheater 27 are arranged between the hydrogen preheating jacket 25 and the inner wall 28 of the reactor; the thermoelectric power generation system 26 is a thermoelectric power generation plate attached to the outer surface of the inner shell of the reactor with a special high thermal conductivity adhesive.

[0022] A further technical solution of the present invention is that the double helix stirring system 1 is composed of a clockwise rotating helix stirrer and a counterclockwise rotating helix stirrer nested together. The double helix stirrers are driven by gears or sprockets at the feed end and rotate in opposite directions, so that the magnesium metal and catalyst powder are fully stirred and reacted with hydrogen. The magnesium-magnesium hydride powder is continuously pushed towards the tail of the reactor and output from the discharge system to the outside of the reactor.

[0023] A further technical solution of the present invention is that a preheating chamber 14 and a decompression chamber 15 of the magnesium powder feeding system are arranged below the feeding funnel 13 of the magnesium powder feeding system.

[0024] A further technical solution of the present invention is that a decompression chamber 3 and a cooling box 4 of the magnesium hydride feeding system are arranged above the collecting chamber 5 of the magnesium hydride feeding system, and a mass sensor 7 is arranged at the bottom of the collecting chamber.

[0025] A further technical solution of the present invention is that the thermoelectric power generation system 26 is connected to the output terminal 21 through a wire network.

[0026] A further technical solution of the present invention is that an explosion-proof safety valve 17 is arranged on the tubular main reactor system.

[0027] A further technical solution of the present invention is that the magnesium powder input system consists of a feeding funnel 13 of the magnesium powder feeding system, a catalyst mixing and preheating chamber 14, and a depressurization chamber 15 of the magnesium powder feeding system. The magnesium powder is transported and reacted in a closed space, with the entire process protected by hydrogen or inert gas. The preheating chamber 14 mixes and preheats the magnesium powder with the catalyst and then transports it to the depressurization chamber. The depressurization chamber 15 of the magnesium powder feeding system consists of an inner door leading to the magnesium hydride synthesis chamber, a chamber for holding the mixed powder, and an outer door communicating with the mixing and preheating chamber. Both the inner and outer doors are airtight and do not open simultaneously; they open at set time intervals. When the depressurization chamber is filled with magnesium powder, the outer door is closed, and the inner door is opened to inject hydrogen. When the hydrogen pressure in the depressurization chamber rises to a specified value, or is the same as the hydrogen pressure in the reactor, the inner door is opened to its maximum to inject the mixed powder into the reactor. The inner door is then closed, and the next feeding cycle begins.

[0028] A method for continuous magnesium hydride production, characterized by utilizing a continuous magnesium hydride production system as described in any one of the above claims.

[0029] The magnesium hydride powder synthesized through the reaction is pushed into the feeding and depressurization chamber by the fan blades of a double-spiral stirrer. The inner door of the feeding and depressurization chamber is normally open, but closes at a specified time during feeding, controlled by the system. Then, the outer door of the feeding and depressurization chamber is opened programmatically, and opened to its maximum extent when the pressure is reduced to atmospheric pressure, feeding the magnesium hydride powder into the cooling chamber. The outer door is then closed, and the inner door is opened, starting the next feeding cycle. After the fed magnesium hydride powder cools to a certain temperature, the outer door of the cooling chamber is opened, and the magnesium hydride powder falls into the collection chamber. In the collection chamber, it is quantitatively measured, packaged, and then output, or continuously output through pipelines. The mass sensor in the collection chamber transmits the mass signal to the control center, serving as basic information for controlling the feeding system. The cooling chamber consists of a chamber body and a cooling system, which can be a water-cooling system or an air-cooling system.

[0030] Room temperature hydrogen is first preheated by being injected into the hydrogen channel in the reactor wall through valves and pipes. Then, it is injected into the reactor through a channel set on the inner wall shell to maintain a constant pressure. It works in conjunction with the pump and valve system of the hydrogen constant pressure source to ensure a continuous input of hydrogen and constant pressure. During the preheating process, the hydrogen also cools down the outer wall of the thermoelectric generator, i.e., the cold end, to achieve thermoelectric power generation.

[0031] Room temperature hydrogen is injected into the hydrogen cooling jacket of the reactor shell by a constant pressure source pressure control system and valves and pipelines. It is preheated and then introduced into the reactor. The hydrogen pressure in the reactor is maintained within a specified range by the constant pressure source pressure control system to ensure the continuous progress of the synthesis reaction and the complete conversion of magnesium powder into magnesium hydride.

[0032] A further technical solution of the present invention is that the resistance preheater is distributed alternately with the thermoelectric generator and is closely attached to the outer side of the inner wall of the reactor. When the system is cold started, the resistance preheater 27 is started first to preheat the inner cylinder of the reactor, and during operation, it works in conjunction with the water cooling system to maintain a constant temperature inside the reactor.

[0033] The feeding depressurization chamber functions similarly to the feeding depressurization chamber but operates in reverse: the feeding interval is set by the reactor control system, using time or mass as the unit of measurement. The opening and closing of the feeding depressurization chamber door is controlled by a signal transmitted by a magnesium hydride mass sensor at the bottom of the collection chamber. The pressure in the depressurization chamber is reduced by closing the inner chamber door and opening the outer door in a programmed manner. Once the pressure in the depressurization chamber reaches a specified value, the outer door is opened to its maximum to allow the magnesium hydride to feed into the cooling chamber for cooling. The outer door of the cooling chamber is then closed, and the next feeding cycle begins. The cooling chamber uses a water cooling jacket or an air cooling jacket to cool the magnesium hydride powder.

[0034] Multiple systems work together and are interconnected to precisely control the input, circulation, reaction, and output of powders and gases.

[0035] 1. The present invention, employing the above technical solution, has the following beneficial effects compared to the prior art: The magnesium powder used in the present invention is ultra-high purity industrial magnesium powder, with a purity >99.90%, a particle size of 100-450 mesh, packaged with argon or other inert gas, with no surface oxidation, a bright silver-white color, and no pollution. During the reaction process, hydrogen is supplied at a set pressure (7-10 MPa), and magnesium powder is injected at a set flow rate, and is mixed with and preheated with the catalyst in advance.

[0036] 2. The hydrogen used in this invention is industrial-grade hydrogen with a purity ≥ 99.90%, supplied at a pressure of 10-30 MPa, and operating at a pressure of 7-10 MPa. After startup, the new reactor undergoes a process of evacuation and large-volume hydrogen injection to clean the internal cavity, followed by normal hydrogen injection. The resistance preheater is then activated to raise the temperature and pressure of the injected hydrogen to the specified range, allowing it to fully react with magnesium powder mixed with catalyst to synthesize magnesium hydride. Maintaining the internal hydrogen pressure of the reactor is the control parameter during the reaction; that is, continuous hydrogen input ensures a constant pressure and temperature inside the reactor.

[0037] 3. The following procedure should be followed when shutting down the system: First, drain all the powder from the magnesium hydride synthesis chamber, close the hydrogen constant pressure source valve, close the resistance preheater, increase the cooling water flow rate, and then slowly vent the hydrogen to gradually reduce the pressure in the magnesium hydride synthesis chamber. When the hydrogen venting rate slows down to near atmospheric pressure, open the argon injection valve and continue venting until the magnesium hydride synthesis chamber pressure is slightly higher than atmospheric pressure. Then, close all gas injection and venting valves, maintaining a small flow rate of cooling water until the entire reactor system cools down to near room temperature. During system shutdown, the pressure in the magnesium hydride synthesis chamber should be checked frequently (weekly or at specified intervals) to ensure it is under positive pressure and prevent air intake. For the next startup, there is no need to use a large amount of hydrogen to purge the inner chamber; simply inject hydrogen directly to enter the working state.

[0038] 4. The cylindrical reactor designed in this invention has a multi-layered nested structure, and its effective volume can be set as needed. This design can be used for small experimental reactors (5-20 liters) to industrial reactors (over 10,000 liters). The reactor is designed for a pressure of 12.5 MPa and a temperature of 723 K. During cold start-up, a resistance preheater is used for preheating, with the preheating power determined by the surface area of ​​the magnesium hydride synthesis chamber, approximately 1.5-5.0 KW / m². 2The reactor is coordinated with a water-cooling system to achieve automatic temperature control within the reactor chamber. A significant amount of heat released during magnesium hydride synthesis is recovered via a thermoelectric system, while lower-temperature waste heat that cannot be recovered is output through the water-cooling system to prevent overheating and damage. For ease of maintenance and cost savings, the reactor is temporarily protected by argon gas before shutdown, and hydrogen is injected normally upon restarting to prevent contamination and damage to the magnesium hydride synthesis chamber, pumps, valves, and piping systems, as well as to avoid magnesium oxide contamination of the magnesium hydride.

[0039] 5. The double-helix stirring system designed in this invention can control the speed of powder feeding by controlling its rotation speed, and continuously mix, feed (through the feed depressurization chamber) and discharge (through the discharge depressurization chamber) powder with the basic completion of the hydrogenation reaction as the control factor, so as to avoid the contamination or oxidation of the magnesium hydride powder formed, and ensure the continuous and efficient progress of the synthesis reaction and the continuous output of the reaction products. Attached Figure Description

[0040] To further illustrate the present invention, the following description is provided in conjunction with the accompanying drawings:

[0041] Figure 1 Schematic diagram of an apparatus for the continuous production of magnesium hydride;

[0042] Figure 2 A partially enlarged schematic diagram of the multi-layered nested walls of the reactor vessel;

[0043] The system includes: 1-Double spiral stirring system; 2-Cooling water inlet pipe-valve-pressure gauge system; 3-Pressure relief chamber of magnesium hydride feeding system; 4-Cooling box of magnesium hydride feeding system; 5-Collection chamber of magnesium hydride feeding system; 6-Reaction vessel base; 7-Mass sensor base of collection chamber of magnesium hydride feeding system; 8-Cooling water outlet pipe; 9-Power supply-transformer cabinet; 10-Main shaft-sealing system; 11-Main motor power source of double spiral system; 12-Hydrogen injection system; 13-Feeding system of magnesium powder feeding system. 14-Preheating chamber; 15-Decompression chamber of magnesium powder feeding system; 16-Reactor body; 17-Explosion-proof safety valve of reactor; 18-Argon injection pipe and valve system; 19-Vent valve; 20-Flange of reactor end cover; 21-Output terminal; 22-Outer shell; 23-Water cooling jacket; 24-Intermediate wall; 25-Hydrogen preheating jacket; 26-Thermoelectric power generation system; 27-Reactor resistance preheater; 28-Inner wall of reactor; 29-Magnesium hydride synthesis chamber; 30-Interlayer support plate. Detailed Implementation

[0044] The present invention will be further illustrated below with reference to the accompanying drawings and specific embodiments. It should be understood that the following specific embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. In the description of the present invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," "outer," "top," and "bottom," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention. In addition, unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication of two components. For those skilled in the art, the specific meaning of the above terms in the present invention can be understood according to the specific circumstances.

[0045] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0046] This patent provides multiple parallel solutions; the different descriptions represent improved solutions or parallel solutions based on the basic solution. Each solution has its own unique characteristics. Furthermore, the technical features involved in the different embodiments of the invention described below can be combined with each other as long as they do not conflict with each other. Fixing methods not described herein can be any of the following: threaded fixing, welding fixing, or adhesive bonding.

[0047] To address the aforementioned problems, this invention provides a continuous magnesium hydride production system and method. Through optimized process design, the magnesium hydride synthesis reaction is completed within a closed tubular reactor system. Constant temperature and pressure are maintained throughout the process. An internal double-helix mechanism stirs and propels the powder in a directional manner, ensuring thorough reaction and stable powder transport. Hydrogen gas and magnesium powder mixed with catalyst are injected from the top of the reactor inlet, while the synthesized magnesium hydride powder is discharged from the bottom outlet, achieving continuous synthesis and output of solid magnesium hydride, bringing the production process to an industrial-grade level. Simultaneously, the coordinated control of pressure and temperature throughout the process ensures efficient, safe, low-cost, and high-quality magnesium hydride production.

[0048] This embodiment of the present invention provides a continuous magnesium hydride production system and method. The main body of the system is a hydrogen-filled reactor, and the reactor is equipped with detachable end caps at both ends. (Refer to...) Figure 1 The hydrogen-filled reactor internally consists of a double-helix stirring system, a magnesium powder feeding system, a hydrogen circulation and injection system, an argon injection pipe-valve system, and a magnesium hydride feeding system. Externally, it is equipped with a cooling water system, a power system, a hydrogen constant pressure source, and a central control system. The water cooling pipe system (water inlet and outlet), hydrogen safety valve, hydrogen overflow valve, and argon (or other inert gas) injection valve are all located at convenient installation and maintenance positions on the top of the reactor.

[0049] The aforementioned double-helix stirring system includes a clockwise rotating helical stirrer and a counterclockwise rotating helical stirrer that are interlocked and driven at the feed end by gears or sprockets. The two helical stirrers rotate in opposite directions. The two ends of the double helical stirrers are fixed to the inner wall of the reactor by bearing seats. The main motor of the double helical system provides power to one helical stirrer shaft, and the gears or sprockets on that shaft drive the other helical stirrer shaft to rotate in the same speed but in the opposite direction.

[0050] The magnesium powder feeding system is located directly above the reactor and consists of a feeding funnel, a catalyst mixing-preheating chamber, and a depressurization chamber. Magnesium powder is transported to the funnel through a closed system, and the catalyst is simultaneously injected into the funnel in proportion and falls into the depressurization chamber. The catalyst mixing-preheating chamber completes the mixing and preheating of the catalyst. The feeding depressurization chamber is a small chamber with an inner door leading to the reactor and an outer door leading to the mixing chamber, similar to the extravehicular activity (EVA) mechanism of a spacecraft. The inner and outer doors do not open simultaneously. At a set time interval, when the depressurization chamber is full of magnesium powder, the outer door is closed, and the inner door is opened. Then, when the hydrogen pressure in the depressurization chamber rises to a specified value, the inner door is opened to its maximum extent to inject magnesium powder into the reactor. The magnesium powder funnel and the mixing-preheating chamber are both injected with hydrogen or inert gas, while the depressurization chamber is controllably connected to the magnesium hydride synthesis chamber through an airtight inner door.

[0051] The hydrogen circulation and injection system utilizes a constant-pressure hydrogen source to inject hydrogen into the reactor. Room-temperature hydrogen is first injected into the hydrogen jacket in the reactor wall for preheating, and then directly introduced into the magnesium hydride synthesis chamber. The hydrogen pressure is controlled by a built-in pressure monitoring device, and the constant-pressure hydrogen source and vent pipe-valve system ensure the stability of the hydrogen pressure inside the reactor during production.

[0052] The magnesium hydride feeding system, located at the end of the reactor, is used to output the synthesized magnesium hydride powder. It consists of a depressurization chamber, a cooling chamber, a collection chamber, and a quality sensor for the collection chamber. The quality sensor transmits the quality information of the magnesium hydride in the collection chamber to the central control system, which autonomously decides on the packaging and output actions of the magnesium hydride. The magnesium hydride powder is first pushed to the depressurization chamber by the blades of a double-spiral stirrer. At set time intervals or when the depressurization chamber is full, the inner chamber door is closed, and the outer chamber door is opened to allow hydrogen to leak out and reduce pressure. When the pressure in the depressurization chamber reaches a specified value, the outer chamber door is opened to its maximum, allowing the magnesium hydride to fall into the cooling chamber for cooling, followed by packaging or output. The cooling chamber consists of a cylindrical or square box with a set volume and shape, and its outer shell is composed of a cooling water jacket or an air-cooled jacket.

[0053] The argon injection pipe-valve system is designed to protect the inner layer and internal facilities of the reactor during shutdown. Specifically, before production or maintenance shutdown, as hydrogen is released and the pressure inside the reactor decreases, argon injection is initiated to maintain the pressure in the magnesium hydride synthesis chamber slightly higher than atmospheric pressure, i.e., positive pressure, to prevent negative pressure from drawing in external air and causing contamination and oxidation damage to the inner wall, pumps, valves, and pipes.

[0054] The cooling water system consists of water supply / drainage pipes, valves, pressure gauges, etc. During continuous operation, the heat generated by the thermoelectric power generation and hydrogen preheating cannot be completely consumed by the synthesis reaction. Therefore, a water-cooled jacket is installed on the outer shell to cool down the system, maintain its stability, and prevent overheating. The hot water at the reaction heat outlet can be reused for purposes such as preheating magnesium powder, heating, cooking, and bathroom use.

[0055] The hydrogen-filled reactor provided in this example is a container for the magnesium hydride synthesis reaction. The reactor body is a multi-layered, nested structure, fixed to the reactor base. Power is supplied and transmitted by the power supply-transformer cabinet and the main shaft-sealing system, and an explosion-proof safety valve and flange reinforcement system are added to the reactor system. Figure 2As shown, the reactor vessel itself consists of an outer shell, a water cooling jacket, an intermediate wall, a hydrogen cooling jacket, a thermoelectric power generation system, a reactor resistance preheater, an inner wall, and a magnesium hydride synthesis chamber. The inner wall of the reactor vessel is a high-temperature, high-pressure vessel made of high-temperature, high-pressure resistant vessel steel. The next layer is the thermoelectric power generation system, which uses thermoelectric generators to generate electricity, achieving the dual benefits of fully utilizing the heat of the magnesium hydride synthesis reaction and preheating the hydrogen. The third layer is the hydrogen cooling jacket, a sandwich layer that allows hydrogen to flow from the tail end to the head end of the reactor. The fourth layer is a stainless steel intermediate wall, the fifth layer is a water cooling jacket, and the outermost layer is a stainless steel outer shell. In total, there is one high-temperature pressure vessel, one thermoelectric power generation + preheating layer, two stainless steel jackets, and two cavity layers. The reactor resistance preheater uses resistance heating coils, which can rapidly heat the inner wall of the reactor during system cold starts and, together with the hydrogen circulation and water cooling systems, form a temperature control system to maintain a constant temperature inside the reactor and a lower temperature on the outer layer.

[0056] In summary, this invention discloses a system for the continuous production of magnesium hydride, comprising a cylindrical reactor system, a double-helix stirring system, a magnesium powder input system, a hydrogen circulation and input system, a magnesium hydride discharge system, an argon protection system, a thermoelectric power generation system, a water cooling system, a pressure maintenance system, and a power system. Through optimized process design, the main reactor maintains a constant temperature and hydrogen pressure, and an internal double-helix mechanism stirs and propels the powder in a directional manner. Room temperature hydrogen and preheated hydrogen are injected into the magnesium hydride synthesis chamber through a pipeline-valve system. Magnesium powder mixed with catalyst is injected into the magnesium hydride synthesis chamber from the top depressurization chamber at the reactor inlet. The synthesized magnesium hydride powder is discharged from the reactor outlet.

[0057] The system for continuous production of magnesium hydride provided by this invention can not only continuously and stably synthesize magnesium hydride, but also achieve a hydrogen content of up to 7.6 wt.%. Compared with the magnesium vapor-hydrogen reaction, the magnesium hydride production method proposed in this invention has a lower reaction temperature, lower pressure and is easier to control, and can achieve a conversion efficiency of over 99.5%, realizing the industrial production of magnesium hydride.

[0058] It should be noted that the multiple solutions provided in this patent include their own basic solutions, which are independent of each other and do not restrict each other. However, they can also be combined with each other without conflict to achieve multiple effects.

[0059] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims.

Claims

1. A continuous magnesium hydride production system, characterized in that, The system includes a tubular main reactor system, which includes a reactor body (16). The reactor body has a multi-layer nested structure. The multi-layer nested structure is arranged from the outside to the inside as follows: outer shell (22), water cooling jacket (23), intermediate wall (24), hydrogen preheating jacket (25), thermoelectric power generation system (26), reactor resistance preheater (27), and reactor inner wall (28). The space inside the reactor is a magnesium hydride synthesis chamber (29), which is equipped with a temperature and pressure sensor system. The inner wall is connected to the feeding funnel (13) of the magnesium powder feeding system. The inner wall (28) of the reactor is also connected to the collection chamber (5) of the magnesium hydride discharge system. The water cooling jacket (23) connects the cooling water inlet pipe-valve-pressure gauge system (2) and the cooling water outlet pipe (8); the water cooling system is a sandwich-type inner cavity composed of the intermediate wall of the reactor, i.e., the intermediate shell layer and the outer shell of the reactor (22). The cavity is equipped with a water temperature sensor, as well as a water pump, valve and pipes, which are used to strongly cool the intermediate wall; the water cooling system can also maintain the temperature stability of the system during long-term operation and prevent the system from overheating; The hydrogen preheating jacket (25) is connected to the argon injection pipe, valve system (18) and hydrogen injection system. The hydrogen preheating jacket (25) is connected to the hydrogen injection system (12) through pipes and valves. The constant pressure hydrogen source ensures continuous replenishment of the hydrogen consumed by the magnesium hydride synthesis chamber, so as to ensure the continuous synthesis reaction of magnesium and hydrogen by maintaining constant system pressure. A gas venting system is also provided on the reactor body (16), which includes a pressure reducing valve and a venting valve (19); The magnesium hydride synthesis chamber (29) is equipped with a double helical stirring system (1). The double helical stirring system (1) consists of two opposing rotating helical stirrers-main shaft-sealing system (10) and a double helical main motor power source (11) drive system. The main motor power source drives the stable operation of the double helical stirrers.

2. The continuous magnesium hydride production system as described in claim 1, characterized in that, A thermoelectric power generation system (26) and a reactor resistance preheater (27) are arranged between the hydrogen preheating jacket (25) and the inner wall (28) of the reactor. The thermoelectric power generation system (26) consists of thermoelectric generating plates and high thermal conductivity adhesive attached to the outer surface of the inner shell of the reactor, and is connected by a wire network and outputs power from the output terminal (21).

3. The continuous magnesium hydride production system as described in claim 1, characterized in that, The double-helix stirring system (1) consists of a clockwise rotating helical stirrer and a counterclockwise rotating helical stirrer nested together. The double-helix stirrer is driven by gears or sprockets at the feed end and rotates in opposite directions to fully stir the magnesium metal and catalyst powder and allow them to fully react with hydrogen. It continuously pushes the magnesium-magnesium hydride powder towards the tail of the reactor and outputs it to the outside of the reactor through the discharge system. There is a gap between the outer edge of the helical stirrer blades and the wall of the magnesium hydride synthesis chamber, with the gap being between 0.10 and 1.0 mm, to ensure that the powder can be stirred and directionally conveyed without contacting or colliding with the inner wall of the reactor.

4. The continuous magnesium hydride production system as described in claim 1, characterized in that, Below the feeding hopper (13) of the magnesium powder feeding system are arranged a preheating chamber (14) and a depressurization chamber (15), and a pressure sensor is installed in the depressurization chamber.

5. The continuous magnesium hydride production system as described in claim 1, characterized in that, Above the material collection chamber (5) of the magnesium hydride feeding system are arranged the decompression chamber (3) and the cooling box (4) of the magnesium hydride feeding system.

6. The continuous magnesium hydride production system as described in claim 1, characterized in that, The thermoelectric power generation system (26) outputs the thermoelectric power generated by the thermoelectric generator through the output terminal (21) to the outside of the reactor via a wire network.

7. The continuous magnesium hydride production system as described in claim 1, characterized in that, The tubular main reactor system is equipped with an explosion-proof safety valve (17).

8. The continuous magnesium hydride production system as described in claim 1, characterized in that, The magnesium powder input system consists of a feeding funnel (13) of the magnesium powder feeding system, a catalyst mixing and preheating chamber (14) and a depressurization chamber (15) of the magnesium powder feeding system. The magnesium powder is transported and reacted in a closed space, and the entire process is carried out under the protection of hydrogen or inert gas. The preheating chamber (14) can mix the magnesium powder with the catalyst and transport it to the depressurization chamber. The depressurization chamber (15) of the magnesium powder feeding system consists of an inner door leading to the magnesium hydride synthesis chamber, a chamber for holding the mixed powder, and an outer door connected to the preheating chamber (14). The inner and outer doors are not opened at the same time. The outer door is opened at a set time interval. When the chamber of the depressurization chamber is filled with magnesium powder, the outer door is closed. The inner door is opened to inject hydrogen. When the hydrogen pressure in the depressurization chamber rises to a specified value or is the same as the hydrogen pressure in the reactor, the inner door is opened to the maximum to inject the mixed powder into the reactor. The inner and outer doors are both airtight doors.

9. A method for continuous production of magnesium hydride, characterized in that, Using the continuous magnesium hydride production system according to any one of claims 1-8, The magnesium hydride powder synthesized through the reaction is pushed to the discharge pressure chamber by the fan blades of the double helix stirrer. The inner door of the discharge pressure chamber is in the open state and will be closed after a specified time. Then the outer door of the discharge pressure chamber is opened in the program, and the synthesized magnesium hydride powder is transported to the cooling box in a timed / quantitative manner. After cooling to a certain temperature, the outer door of the cooling box is opened, and the magnesium hydride powder falls into the collection chamber. In the collection chamber, it is quantitatively packaged and then output, or continuously output through pipelines. Room temperature hydrogen is first preheated by being injected into the hydrogen cooling jacket in the reactor wall through valves and pipes, and then injected into the reactor to maintain a constant pressure. It works in conjunction with the pump and valve system of the hydrogen constant pressure source to ensure a constant and continuous input of hydrogen pressure. During the preheating process, the hydrogen also cools the outer wall of the thermoelectric generator, i.e. the cold end, to achieve thermoelectric power generation. Room temperature hydrogen is injected into the hydrogen cooling jacket of the reactor shell by a constant pressure source pressure control system and valves and pipelines, and is preheated before being introduced into the reactor. The hydrogen pressure in the reactor is maintained within a specified range by the constant pressure source pressure control system to ensure the continuous progress of the synthesis reaction and the complete conversion of magnesium powder into magnesium hydride.

10. The method for continuous production of magnesium hydride as described in claim 9, characterized in that, The resistance preheating system consists of resistance preheaters distributed alternately with thermoelectric generators and surrounding the outer side of the inner wall of the reactor. During the cold start of the system, the preheaters are activated first to preheat the inner cylinder of the reactor, and during operation, they work together with the water cooling system to maintain a constant temperature inside the reactor. The material discharge decompression chamber has a similar function to the material feeding decompression chamber, but the operation procedure is reversed: it can preset the material discharge interval, with time or mass as the unit of measurement. By closing the inner chamber door and opening the outer chamber door in a programmed manner, the pressure in the decompression chamber is reduced. Once the pressure in the decompression chamber reaches the specified value, the outer door of the decompression chamber is opened to the maximum to allow magnesium hydride to discharge and enter the cooling box for cooling; the cooling box is cooled by a water cooling jacket for magnesium hydride powder. Multiple systems work together and are interconnected to precisely control the input, circulation, reaction, and output of powders and gases.

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